1. Field of the Invention
The present invention relates to an image recording apparatus in which an image on an original document is copied onto a photosensitive material by exposure, and the photosensitive material and an image receiving material are superposed on each other for heat development/transfer, thereby producing an image on the image receiving material.
2. Description of the Related Art
An image recording apparatus for producing a color image has been known in which an image on an original document is copied onto a photosensitive material by exposure, and an image receiving material is superposed on the photosensitive material to cause the photosensitive material to closely contact the image receiving material for heat development/transfer, thereby producing an image on the image receiving material.
It is well known to dispose an original document and a photosensitive material facing each other, to fixedly provide an optical system as an exposure unit, and to move the original document and the photosensitive material so as to expose the photosensitive material. Also, it is well known to fixedly dispose an original document and a photosensitive material, and to move an optical system in parallel with the original document and the photosensitive material between them. In both cases, a light beam having a slit-like cross section is irradiated from a light source provided in the optical system toward an original document and is reflected by the original document. The light reflected by the original document successively irradiates different portions of the photosensitive material.
In the mechanism in which an original document and a photosensitive material are moved (transported), a highly accurate speed control is required for movements of the original document and the photosensitive material to obtain a high resolution. Further, a highly accurate transport is required to prevent generation of a shift between the original document and the photosensitive material. These requirements increase costs.
Although the mechanism in which the optical system is moved can solve the above-described drawbacks, the size of the optical system must be decreased, because the optical system is moved within a narrow space between the original document and the photosensitive material. However, the necessity of color adjustment and density adjustment makes it difficult to decrease the size of the optical system.
For example, in the case where a halogen lamp is used as a light source, color separation filters for three colors, i.e., C (cyan), M (magenta) and Y (yellow) are necessary, and these Filters increase the size or the apparatus.
An original document is placed on a platen glass, and covered with a document cover. However, when the cover is opened or when the cover is closed in a lifted state, external light enters and causes light fogging of a photosensitive material.